Proposals have been made in the past to provide a pumping system which would automatically sense the presence of liquid and then pump them from one location to another. One such device, which has been in use for years is the combining of an air-driven double diaphragm pump and a pneumatic bubbler/air valve. This kind of system is available from Air Pump Company of Grand Blanc, Michigan, USA. This system requires the use of a double diaphragm pump which is generally larger than 12 inches in diameter and is used to suck fluids from one location and push them to another. This type of system is limited since it can only draw fluid up from about 25 feet depth and to reach greater depths, the pump must be lowered into a rather large well, sump or opening. In addition, the nature of the pump's mechanical action makes it an inefficient pump to use.
Another system utilizes internal controls to operate pneumatic valves and pressurize and exhaust the pump based upon the fullness of the pump. Such a system is disclosed in U.S. Pat. No. 4,467,831 to French, issued August 28, 1984. This system utilizes a displacer to load and unload spring-loaded opposing poppets and thus cause the pump body to pressurize and exhaust. This system has several inherent defects which make the use of the system fraught with maintenance and control problems. A delicate balance between the displacer weight, spring tension and friction which holds the poppets to the o-rings, in which they seat must be maintained if the pump is to function. Too much pressure on either the lower or upper poppet can cause the poppet to jam into the o-ring and "freeze" the pump. If the pressure is not great enough on the upper poppet, the spring tension can lift it off its seat and cause air to constantly stream into the pump and out its exhaust. In practice the pressure range in which this design can operate when the pump must operate within a 4-inch well casing or smaller spans about 40 psi. If the pressure to be used falls or rises outside of this range, the internals of the pump must be adjusted to accommodate such operation or the pump will fail to operate This can be a severe problem if the pressure to the pump fluctuates or the head against which the fluid is being pumped increases. In addition, when the pump is introducing pressurized air into the pump chamber to push out fluid, some of this air bleeds off out the exhaust. This causes a loss of energy. If the pump is constructed so that fluid enters through a check valve at the base of the pump, a fast influx of fluid can unweight the displacer and cause the poppets to shift. When this happens, pressurized air forces the fluid out of the pump, moving the displacer down and reseating the poppets. This action is repeated rapidly and a "stuttering" or "quick cycle" is developed. When this condition is reached, the pump rate and efficiency decreases dramatically. In addition, the friction of the o-rings against the poppets can change if the chemicals which are being pumped cause the o-rings to become lubricated or swell. This can cause the valving mechanism to shift too soon or not at all.
None of the pumping systems described above discloses apparatus and method for pumping fluid which uses a float inside of a canister which trips a pivot arm and thus alternately pressurizes and exhausts a pump chamber. None of the above systems are designed such that they can operate inside of a small volume such as a 4-inch internal diameter well casing at pressures ranges from 10 to 125 psi without adjustment to the mechanisms of operation.
None of the above systems described disclose apparatus and method which utilize a pivot arm which action opens and closes the air valves and after it has been set in motion via the travel of the float, it will complete its travel thus switching the valves which either pressurize or exhaust the pump chamber.
None of the above systems described disclose apparatus and method which has direct air contact against the fluid being pumped and does not cause a bleed of compressed air out of the exhaust of the pump when the pump is pressurizing the pump chamber.
None of the above systems described disclose apparatus and method which has direct air contact against the fluid being pumped and prevents the rapid stuttering of the pumping mechanism if fluid were to rush into a lower check valve after the pump was exhausted of compressed air.